Just as California begins its final marketing push to get people signed up for health coverage by the end of March, the portal for the state's exchange has been shut down because of software problems.

Covered California officials took the exchange's enrollment portal offline Wednesday afternoon and it has been down ever since.

It's a case of bad timing for Covered California officials, with a little more than a month before the March 31 enrollment window closes.

Earlier this week, the agency unveiled its latest enrollment figures, which showed that the exchange is meeting its targets and that more than 828,000 Californians had enrolled in private health plans as of Feb. 14.

But officials acknowledged they needed to push harder to attract Latinos, who are considered a key demographic for the program. Latinos are uninsured at higher rates than other ethnicities in the state, but tend to be younger and healthier than the general population. So their participation in the larger health insurance pool is seen as a way to help lower rates for everyone.

The agency had just announced an $8.2 million Spanish-language advertising campaign through the end of next month when its enrollment tool shut down. In a statement issued Friday, exchange officials said engineers were working around the clock to fix the problem. They did not say when the site would be up and running again.

Covered California did not go into detail about the software malfunction. The release said "intermittent errors with the enrollment pages" ended some sessions during the application process.

While Covered California has not had the same level of problems that have plagued the federal government's portal, the state has experienced some online glitches, paperwork delays and long wait times for help on the phone.

Adding to its February woes, Covered California this month had to take its physician directory offline until further notice because of errors and also suspended its small business enrollment portal.

In a release issued Friday, exchange officials said consumers can still visit Covered California's website for information and use the "shop and compare tool." But consumers won't be able to enroll online.